The family's origins date back as far as 6th century England, when Sir Brian Kent participated in several adventures under the pseudonym the Silent Knight. On at least one occasion, he met a time-traveling Superman and it has been suggested that Sir Brian may have been the progenitor of the Kent family line.
The Kents first emigrated to the Americas in the late 18th Century. The American Kents originally hailed from Boston, Massachusetts where print-shop owner Silas Kent lived with his wife Abigail. The two sired eight children, all of whom were born in the Kent's Boston home. In 1854, Silas Kent joined the Emigrant Aid Society and decided to relocate his printing press to Lawrence, Kansas to promote his abolitionist ideals. He brought his two oldest sons, Nate and Jeb along with him. Unfortunately, the family patriarch was murdered by Border Ruffians who wanted to silence him. Furthermore, the sons, Nathaniel and Jeb, argued and had a parting of the ways so deep about slavery that they found themselves on opposing sides of the American Civil War, with Jeb fighting with the notorious Confederate guerrilla unit led by William Quantrill and Nathaniel fighting for the North and marrying a half-Native American woman who gave him a special traditional spiritual symbol that was apparently a forerunner and inspiration for Superman's chest symbol.
After the war, Nathaniel became a sheriff in Smallville, while Jeb became the leader of a group of bandits. Eventually, Jeb discovered he had a son out of wedlock years ago, and allowed him to join his gang. Unfortunately, his son turned out to be a murderous sociopath and Jeb approached his estranged brother to arrange a trap to stop his son.
In springing the trap, the son mortally wounded his father before being killed himself and Jeb has just enough time to fully reconcile with Nate before dying. Nate remained in Smallville and there the Kents have since stayed for generations.